This invention relates to a concrete well casing and more particularly to a concrete well casing having centralizers secured thereto which center or centralize the well casing within a well bore hole.
Concrete well casing is ordinarily positioned in a well to prevent the walls of the well from collapsing. The concrete well casings normally are comprised of a cylindrical wire mesh which is embedded in concrete. A predetermined portion of the well casing string is perforated to permit water to enter the interior of the casing.
The customary manner of positioning the casing members in a well is to lower the same by means of casing cables. Applicant has been previously granted U.S. Pat. No. 4,070,832 which provided a concrete well casing with cable hooks embedded therein to facilitate the lowering of the casing into the well. A problem still exists in the positioning of the casing members within the bore hole when the diameter of the bore hole is greater than the outside diameter of the casing member. The customary practice at present is to secure a plurality of boards such as 2.times.4's to the exterior surface of certain of the casing members so that the boards will engage the wall surface of the bore hole to centralize or center the casing with respect to the well bore hole. The necessity of securing boards to the casing is not only time consuming but is quite expensive. A further problem with the use of boards is that the width of the boards combined with the diameter of the casing is either too great or too small for the particular bore hole.
Therefore, it is a principal object of the invention to provide a concrete well casing having centralizers secured thereto and integrally formed therewith.
A still further object of the invention is to provide a concrete well casing having centralizers secured thereto which may be selectively adjusted to correspond to the diameter of the bore hole.
A still further object of the invention is to provide a concrete well casing having centralizers secured thereto which do not interfere with the fabrication of the casing.
A still further object of the invention is to provide a concrete well casing having centralizers mounted thereon which is economical of manufacture and durable in use.
These and other objects will be apparent to those skilled in the art.